System and method for measuring dissolved metal concentrations using a chemosensor film

Abstract

A system for analyzing a chemosensor that includes a light source directed at a chemosensor, and a spectrometer arranged to detect a signal from the light source after passing through the chemosensor. The spectrometer includes signal conditioning electronics and spectral decomposition software which allows the spectrometer to perform a spectral analysis in order to identify, in real time, one or more heavy metals in a continuous flow of water interacting with one or more dyes on the chemosensor.

What is claimed is: 
     
       1. A system for measuring dissolved metal concentrations using a chemosensor, the system comprising:
 a light source; and 
 a spectrometer arranged to detect light from the light source after the light passes through the chemosensor; 
 wherein the spectrometer includes signal conditioning electronics and spectral decomposition software which allows the spectrometer to perform a spectral analysis to identify, in real time, one or more heavy metals dissolved in a continuous flow of water interacting with one or more dyes on the chemosensor 
 wherein the spectral decomposition software is configured to use a partial least squares model built from calibration data; and 
 wherein the spectral decomposition software computes a time-averaged concentration of heavy metals in a flow of water based on a calculation of the accumulated metal on the chemosensor. 
 
     
     
       2. The system of  claim 1 , further including an aperture disposed between the light source and chemosensor. 
     
     
       3. The system of  claim 1 , further including a pump to facilitate the continuous flow of water across the chemosensor at a controlled flow rate. 
     
     
       4. The system of  claim 1 , wherein the spectrometer includes communications circuitry to transmit spectral analysis data to a local or remotely located user interface device. 
     
     
       5. The system of  claim 4 , wherein the user interface device is one of a smartphone, tablet computer, mobile computer, industrial human machine interface (HMI) a dedicated single-board computer interface, and desktop computer. 
     
     
       6. The system of  claim 1 , further including a source for a sensor regeneration reagent, wherein the sensor regeneration reagent removes all metals bound to the chemosensor. 
     
     
       7. The system of  claim 1 , further including a source for a sensor recalibration reagent, wherein the sensor recalibration reagent is configured to flush regenerating reagent out of the chemosensor and to facilitate a baseline spectral calibration of the chemosensor. 
     
     
       8. The system of  claim 1 , further including a degassing unit to remove dissolved gases from the flow of water before interaction with the chemosensor. 
     
     
       9. The system of  claim 1 , further including an n-way selector valve positioned upstream of the chemosensor, the n-way selector valve configured to selectively supply any one or any combination of “n” liquids to the chemosensor, where “n” is a number greater equal to, or greater than, two. 
     
     
       10. The system of  claim 9 , further including a mixer positioned between the n-way selector valve and the chemosensor. 
     
     
       11. The system of  claim 1 , wherein the spectral analysis is able to identify the presence of one or more of iron, copper, cadmium, tin, silver, chromium, cobalt, lead, manganese, mercury, zinc, and nickel in the water flowing across the chemosensor. 
     
     
       12. The system of  claim 1 , wherein the spectral analysis is able to specify the concentration of one or more of iron, copper, cadmium, tin, silver, chromium, cobalt, lead, manganese, mercury, zinc, and nickel in the water flowing across the chemosensor. 
     
     
       13. A method of measuring dissolved metal concentrations using a chemosensor comprising the steps of:
 providing a flow of water across the chemosensor which has one or more dyes each configured to change colors due to interaction with a specific type of metal; 
 directing light from a light source at the chemosensor while the flow of water is flowing across the chemosensor; 
 performing a spectral analysis of the light passing through the chemosensor; 
 determining, in real time based on the spectral analysis, a concentration of one or more metals dissolved in the flow of water; 
 using a partial least squares model built from calibration data to determine an amount of metal accumulation on the chemosensor based on data from the spectral analysis; and 
 calculating a time-averaged concentration of heavy metals in a flow of water using a water flow rate, an elapsed time, and the amount of metal accumulation on the chemosensor. 
 
     
     
       14. The method of  claim 13 , further comprising the step of degassing the flow of water to remove dissolved gases before the flow of water interacts with the chemosensor. 
     
     
       15. The method of  claim 13 , further comprising the step of regenerating the chemosensor prior to providing the flow of water across the chemosensor. 
     
     
       16. The method of  claim 13 , further comprising the step of washing the chemosensor to flush out acids prior to providing the flow of water across the chemosensor. 
     
     
       17. The method of  claim 13 , wherein directing light from a light source at the chemosensor comprises directing light through an aperture at the chemosensor. 
     
     
       18. The method of  claim 13 , wherein identifying in real time one or more metals dissolved in the flow of water comprises identifying one or more of iron, copper, cadmium, tin, silver, chromium, cobalt, lead, manganese, mercury zinc, and nickel. 
     
     
       19. The method of  claim 13 , further comprising transmitting spectral analysis data to a local or remotely located user interface device. 
     
     
       20. The method of  claim 13 , wherein providing a flow of water across the chemosensor comprises pumping a flow of water across the chemosensor at a known flow rate.